time capsule
A sealed container of today’s items saved for the future.
A time capsule is a container filled with objects from the present that people seal up and hide away, planning to open it many years in the future. The idea is to give future people (or your future self) a snapshot of what life was like at a particular moment in time.
Schools sometimes create time capsules when a new building opens, filling them with student artwork, popular toys, newspapers, photographs, and letters describing daily life. They might bury the capsule in a cornerstone with instructions to open it in 50 or 100 years. Families occasionally make their own time capsules, perhaps burying a box in the backyard with birthday cards, favorite books, and notes about current events.
When a time capsule gets opened decades later, it becomes like a little museum exhibit from the past. People discover old technology that seems quaint or funny (imagine someone in 2070 finding your smartphone!), read about concerns and hopes that matter differently now, and see how ordinary life has changed. The objects themselves might not be valuable, but they tell stories about how people lived, what they cared about, and what they thought the future would be like.
Sometimes people accidentally create time capsules without meaning to, like a shoebox of letters tucked in an attic or a journal buried in a drawer, waiting to surprise someone years later.